Selectivity in the Interaction of Electron Donor and Acceptor Molecules with Graphene and Single-Walled Carbon Nanotubes

Varghese, Neenu; Ghosh, Anupama; Voggu, Rakesh; Ghosh, Sandeep; Rao, C. N. R.

doi:10.1021/jp9075355

Cited by 66 publications

(64 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This is not surprising, given the fact that undoped graphene is electron rich due to the delocalized π (e -) charge cloud on it. This observation is consistent with the higher interaction energy of TCNE with graphene (FG) compared to TTF as measured calorimetrically [23].…”

Section: Resultssupporting

confidence: 86%

XPS evidence for molecular charge-transfer doping of graphene

Choudhury

Das

Sarma

et al. 2010

Chemical Physics Letters

116

View full text Add to dashboard Cite

By employing x-ray photoelectron spectroscopy (XPS), we have been able to establish the occurrence of charge-transfer doping in few-layer graphene covered with electron acceptor (TCNE) and donor (TTF) molecules. We have performed quantitative estimates of the extent of charge transfer in these complexes and elucidated the origin of unusual shifts of their Raman G bands and explained the differences in the dependence of conductivity on n-and p-doping. The study unravels the cause of the apparent difference between the charge-transfer doping and electrochemical doping.2 Introduction:

show abstract

Section: Resultssupporting

confidence: 86%

XPS evidence for molecular charge-transfer doping of graphene

Choudhury

Das

Sarma

et al. 2010

Chemical Physics Letters

116

View full text Add to dashboard Cite

show abstract

“…The increase in E ads observed for the adsorption of R-DMBI onto 555-777 defective graphene is accompanied by a larger charge transfer. In this sense, 8 we found that at the M06-L/6-31G* level, 0.87 e-are donated by R-N-DMBI. In the same line, Mulliken spin densities revealed that 1.0 e-is donated by R-N-DMBI.…”

Section: Resultssupporting

confidence: 48%

Strong N-Doped Graphene: The Case of 4-(1,3-Dimethyl-2,3-dihydro-1H-benzoimidazol-2-yl)phenyl)dimethylamine (N-DMBI)

Denis

Iribarne

2015

J. Phys. Chem. C

View full text Add to dashboard Cite

By means of first principle calculations, we investigated the effects of the adsorption of the strong ntype dopant 4-(1,3-dimethyl-2,3-dihydro-1 H-benzoimidazol-2-yl)phenyl)dimethylamine (N-DMBI) onto graphene. The adsorption of radical N-DMBI (R-N-DMBI) occurs with large adsorption energy (E ads ) of 44.4 kcal/mol and induces a metallic character on graphene by shifting the Dirac point 0.6 eV below the Fermi level. The charge received by graphene can be almost completely removed and thus the metallic character may be inhibited, if 2,3,5,6-tetrafluoro-7,7,8,8-tetra-cyanoquinodimethane (F4-TCNQ) is simultaneously adsorbed on any side of graphene. In effect, by doing so, the semimetallic character is recovered or a tiny gap is opened. When F4-TCNQ and radical N-DMBI are adsorbed on the same side, the molecules are strongly held together thanks to the hydrogen bond formed between the fluorine atoms of F4-TCNQ and the H of R-N-DMBI. In this case, the E ads is over 120 kcal/mol, per F4-TCNQ/R-N-DMBI pair. When the latter two molecules are adsorbed on opposite sides, the E ads is 87.6 kcal/mol. This value is more than 30 kcal/mol smaller than that computed when they are adsorbed on the same side, even though it is nearly 10 kcal/mol larger than the sum of the E ads of isolated F4-TCNQ and R-N-DMBI. In this case, graphene behaves as a medium which transfers electrons from R-N-DMBI to F4-TCNQ, without having the molecules in direct contact. We see a strong synergic interaction that increases the E ads when an electron donating molecule is combined with an electron withdrawing one. R-N-DMBI has a profound influence on the reactivity of graphene. Bond energies between the graphene surface and H, F and OH radicals increased when R-N-DMBI is adsorbed, but the addition of these radicals destroys the metallic character of the graphene-R-N-DMBI complex and band gaps in the range of 0.2-0.4 eV are opened. These results show that the radical N-DMBI alters the chemistry and electronic properties of graphene to an extent which rivals the most popular molecules and substrates used in the non covalent chemistry of graphene.

show abstract

“…25 Adsorption of small organic molecules such as ethanol, acetone, acetonitrile, and toluene on the graphene surface has been studied both experimentally and theoretically. 27,28 Hybrid materials derived from graphene quantum dots exhibit excellent gas sensing ability. 27,28 Hybrid materials derived from graphene quantum dots exhibit excellent gas sensing ability.…”

Section: Introductionmentioning

confidence: 99%

Optical response and gas sequestration properties of metal cluster supported graphene nanoflakes

Chakraborty

Chattaraj

2016

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

The possibility of obtaining metal cluster (M3O(+), M = Li, Na, K) supported pristine, B-doped and BN-doped graphene nanoflakes (GR, BGR and BNGR, respectively) has been investigated by carrying out density functional theory (DFT) based calculations. Thermochemical analysis reveals the good stability of M3O(+)@GR/BGR/BNGR moieties. The dynamic stability of M3O(+)@GR/BGR/BNGR moieties is confirmed through an atom-centered density matrix propagation simulation at 298 K up to 500 fs. Orbital and electrostatic interactions play pivotal roles in stabilizing the metal-cluster supported graphene nanoflakes. The metal clusters lower the Fermi levels of the host nanoflakes and enable them to exhibit reasonably good optical response properties such as polarizability and static first hyperpolarizability. In particular, Na3O(+)/K3O(+)@BGR complexes exhibit very large first hyperpolarizability values at the static field limit. All the M3O(+)@BGR/BNGR moieties demonstrate broadband optical absorption encompassing the ultraviolet, visible as well as infrared domains. The metal-cluster supported graphene nanoflakes, in general, can sequestrate polar molecules, viz. CO, NO and CH3OH, in a thermodynamically more favorable way than GR, BGR and BNGR. In the adsorbed state, the CO, NO and CH3OH molecules, in general, attain an 'active' state as compared to their free counterparts.

show abstract

Selectivity in the Interaction of Electron Donor and Acceptor Molecules with Graphene and Single-Walled Carbon Nanotubes

Cited by 66 publications

References 27 publications

XPS evidence for molecular charge-transfer doping of graphene

XPS evidence for molecular charge-transfer doping of graphene

Strong N-Doped Graphene: The Case of 4-(1,3-Dimethyl-2,3-dihydro-1H-benzoimidazol-2-yl)phenyl)dimethylamine (N-DMBI)

Optical response and gas sequestration properties of metal cluster supported graphene nanoflakes

Contact Info

Product

Resources

About